System test addzone "I:checking rndc showzone with newly added zone" elicits the following: 09-Nov-2017 18:40:58.888 received control channel command 'showzone added.example in external' 09-Nov-2017 18:40:58.888 mdb_txn_begin: MDB_BAD_RSLOT: Invalid reuse of reader locktable slot bind9-master-freebsd11-32 on jenkins